The invention concerns a light box.
Light boxes serve for the affixation of posters. They consist of a box sealed by means of a diffuser panel which normally contains several fluorescent lamps. Posters affixed to the diffuser panel are back-lit by the fluorescent lamps. If the box is deep enough, the lamps can be fitted at a distance from the diffuser panel, but difficulties arise if the box is not very deep. In such cases the light diffusion is uneven, with the result that the position of the lamps can be identified from the outside through the diffuser panel and poster. Places with greater luminance than their surroundings are known as hot spots. The desired effect, of course, is one of optimal even back-lighting of the poster, i.e. even illumination of the diffuser panel.